There is a growing concern with the quality of water available for home and industrial consumption. The standard water supply sources such as reservoirs, lakes and underground wells are becoming increasingly subjected to pollution. As more open land is converted from its natural state to residential and industrial development, there is less natural purification of water, but there are a greater number of sources producing pollution in the form of increased soil erosion and the greater distribution of chemicals such as pesticides and herbicides. As a result, the municipal water supplies are receiving substantially more pollution than in past years and only a portion of this pollution is removed through the treatment facilities utilized by community water systems.
Most water treatment today is directed toward the injection of chlorine to kill bacteria rather than to the removal of particulate matter and various types of chemical pollution. Water purification is most effectively and economically carried out just before its ultimate consumption. This results in filtration only of that water which is to be actually consumed. But the cost of filtering water can become substantial when filter elements are replaced each time they become clogged. Therefore, there is a need for a water filter which can be easily connected at a user location and which is designed to be readily back washed to reduce the cost of operation and thereby eliminate the need for replacing filter elements.